Electrical connector insulator block construction



s. w. DEAN 3,072,340

ELECTRICAL CONNECTOR INSULATOR BLOCK CONSTRUCTION Jan. 8, 1963 5 Sheets-Sheet 1 Filed Sept. 16. 1960 I'lllllil B INVENTOR. 6010ON 7V: DER/V BY a flrraEA/E vs.

Jan. 8, G. W. DEAN ELECTRICAL CONNECTOR INSULATOR BLOCK CONSTRUCTION Filed Sept. 16, 1960 5 Sheets-Sheet 2 .muzmmz. 60200 W -DE/w Jan. 8, 1963 G. w. DEAN 3,07

ELECTRICAL CONNECTOR INSULATOR BLOCK CONSTRUCTION Filed Sept. 16, 1960 5 Sheets-Sheet 3 INVENTOR. Goeaav 7V; Den/v Maid/0M Jan. 8, 1963 G. w. DEAN 3,072,340

ELECTRICAL CONNECTOR INSULATOR BLOCK CONSTRUCTION Filed Sept. 16, 1960 5 Sheets-Sheet 4 \20 1 1 6. 21; INVENTOR.

/ I I54 40 fibeoo/v 7V: DEHN ELECTRICAL CONNECTOR INSULATOR BLOCK CONSTRUCTION Filed Sept. 16, 1960 G; w. DEAN 5 Sheets-Sheet 5 Jan. 8, 1963 2% i ig Q INVENTOR.

60200 m DEA-W BY z r a 7 flrTQm/EY w w w @w wfl I N United States Patent ()filice 3,072,340 Patented Jan. 8, 1963 3,072,346 ELEQTRICAL CONNECTQR HNSULATOR BULNIK CONSTRUQTEON Gordon W. Dean, Alhambra, Caiifi, assignor to Cannon Electric Company, Los Angeles, Calif., a corporation of California Filed Sept. 16, 1960, Ser. No. 56,561 7 Claims. (Cl. 339-49) The present invention relates to electrical connectors, and it relates particularly to insulator members employed therein.

It is an object of the present invention to provide a novel electrical connector insulator block for supporting a plurality of contact terminals, wherein the block is of hermaphrodite construction, i.e., is mateable with an identical insulator block member, so that the same insulators may be employed in both the plug and receptacle portions of the connector.

Another object of the present invention is to provide an electrical connector insulator block of hermaphrodite design for carrying a plurality of contact terminals which, when mated with an insulator block of identitcal construction so as to provide electrical connection between the contact terminals of their respective insulators, will completely enclose the contact terminals within the insulators, and will separate the individual contact terminals from each other, thus minimizing the likelihood of flashover.

Another object of this invention is to provide electrical connector insulator members of the character described which have a new modular construction perniitting them to be stacked together in a wide variety of combinations. It is also an object of the invention to provide novel snap-on strap means for securing stacks or blocks of these modular insulator members together and for removably securing the insulator modules within plug and receptacle shells, and to provide novel plug and receptacle shells for supporting these stacks or blocks of modular insulator members.

It is a further object of the present invention to provide hermaphrodite insulator modules of the character described in combination with contact members which are likewise of hermaphrodite construction and which may be snapped into respective openings in the insulator modules, whereby not only the insulator modules but also the contact members are of the same construction for both the plug and socket portions of the electrical connector. These novel hermaphrodite contacts which are preferably employed in connection with the insulator modules have interengaging inclined spring contact fingers tending to draw the opposed contacts together, thus tending to draw and hold opposed insulator modules and hence the plug and receptacle connector members together without requiring separate latching means on the plug and receptacle shells for most uses. Contact terminals of this type are described and claimed in my copending application Serial No. 792,287, now Patent No.

3,011,143, for Electrical Connector.

The insulator modules cannot be engaged with each other unless they are properly oriented, whereby positive polarization is provided \by the insulator modules themselves, either for a single pair of the modules or for a plurality of stacked modules in each of the connector members in any of the many different arrangements of the modules.

A general object of this invention is to provide electrical connector members of the aforesaid character which, because of the use of only a single type of insulator module and contact terminal, is simple and economical to manufacture, yet which is highly flexible and reliable in operation and will accommodate any desired number of contacts within a minimum of space, being particularly useful for such complex connector applications as in computers and business machines.

Further objects and advantages of the invention will appear during the following part of this specification wherein the details of construction and mode of operation of a preferred embodiment are described with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view showing a wall or panel installation of the connector with the plug and receptacle portions engaged.

FIG. 2 is a perspective view showing the plug and receptacle portions of the connector separated from each other, each portion of the connector member embodying a stack or block comprising three individual insulator modules.

FIG. 3 is a perspective view showing a pair of the individual insulator modules in axially aligned, opposed relationship ready to be engaged with each other.

FIG. 4 is a front elevational view of one of the insulator modules.

FIG. 5 is a side elevational view of an insulator module.

FIG. 6 is a rear elevation of an individual module.

FIG. 7 is a vertical section taken on the line 7-7 in FIG. 4.

FIG. 8 is a horizontal section taken on the line 8-8 in FIG. 4.

FIG. 9 is a fragmentary horizontal section taken on the line 99 in FIG. 4.

FIG. 10 is an expanded perspective view illustrating three of the insulator modules stacked side-by-side, with a pair of mounting strap members for holding the modules together and snapping them into position in a plug or socket shell being shown in spaced relation to the modules.

FIG. 11 is a detail section taken on the line 11--11 in FIG. 10 illustrating the spring finger means on one of the mounting straps for latching the straps within a plug or receptacle shell.

FIG. 12 is a perspective view illustrating an insulator module with single insulator mounting straps operatively positioned thereon.

FIG. 13 is a fragmentary vertical section along the line 13-13 in FIG. 12.

FIG. 14 is a front elevation view of the receptacle shell shown in FIGS. 1 and 2.

FIG. 15 is a side elevation view, partly in section, of the receptacle shell shown in FIG. 14.

PEG. 16 is a horizontal section along the line 1616 in FIG. 14.

MG. 17 is an enlarged fragmentary section showing a portion of the receptacle shell as illustrated in FIG. 16, with an insulator module and mounting strap operatively positioned therein.

FIG. 18 is a front elevation view of the plug shell shown in FIGS. 1 and 2.

FIG. 19 is a vertical section along the line 19--19 in FIG. 18.

FIG. 19:: is a horizontal section along the line 19a19a in FIG. 19, illustrating details of construction of the cable clamping means embodied as a part of the plug shell.

FIG. 20 is a perspective view of a preferred contact terminal employed in the present invention, before attachment of a conductor thereto as by crimping.

FIG. 21 is a top plan view of the terminal shown in FIG. 20 with a conductor crimped thereto.

FIG. 22 is an axial section along the line 22-22 in FIG. 21.

FIG. 22a is a transverse section along the line 22a22a in FIG. 22.

FIG. 23 is an enlarged, fragmentary vertical section illustrating a pair of opposed, axially aligned insulator 3 modules with the contact terminals operatively positioned therein, the right-hand module of FIG. 23 corresponding to the module illustrated in FIG. 7 and being viewed along a similar section line.

FIG. 24 is a sectional view similar to FIG. 23 with the insulator modules and contact terminals operatively interengaged.

FIG. 25 is a diagrammatic view illustrating various alternative positions of from one to four of the insulator modules; FIG. 25a illustrating two positions for one module, FfG. 25b showing eight positions for two modules, FIG. 25c showing twenty-four positions for three modules, and FIG. 25d illustrating eighty different positions for four of the modules.

Referring to the drawings, and at first particularly to FIGS. 1, 2 and 3 thereof, the connector 10 which is illustrated includes a receptacle connector member 12 and a plug connector member 14. The receptacle connector member 12 includes a generally rectangular shell 16 having an insulator block or stack 18 therein, the particular receptacle shell illustrated containing three individual insulator modules 20 which are stacked side-by-side to form the stack 18. It will be appreciated that this number of modules 20, and the arrangement thereof, are for purposes of illustration of the invention, and that any number of the modules and any arrangement thereof may be supported together in stacked relationship in the receptacle shell. Thus, one, two, three, four, or a larger number of the modules 20 may be contained in the receptacle shell, and may be stacked in any of a wide variety of difierent ways.

The illustrated receptacle shell 16 has an outwardly directed flange 22 at its front edge to serve as a means for mounting the receptacle member 12 on a panel or wall 24. The shell 16 also includes one or more keyways 26 for polarization of the receptacle and plug connector members. Further polarization is accomplished by the fact that each of the insulator modules can only be interengaged with another module in one relative position of orientation, as will be apparent from the following description.

The plug connector member 14 includes a generally rectangular shell 28, the forward portion of which is engageable within the receptacle shell 16. The same number of insulator modules 20 are supported within plug shell 28 as in receptacle shell 16, and are turned 180 about the axis along which the connector members mate so as to be engageable with the complementary modules 20 in the receptacle shell 16. Accordingly, the insulator block or stack 30 in the plug shell 28 comprises three of the individual insulator modules 29 stacked side-by-side. The plug shell 28 includes one or more external polarizing keys 32 adapted for slidable engagement within the receptacle keyways 26.

A cable 34 comprising a plurality of individual electrical conductors 36 has been shown in FIG. 2 in connection with the receptacle connector member 12, the individual conductors 36 entering the receptacle shell 16 through the rear thereof, the conductors 36 being adapted for connection to the respective contact terminals which are to be disposed within the insulator modules. Similarly, a cable 38 comprising a plurality of conductors 40 has been illustrated in FIG. 2 in operative position relative to the plug connector member 14.

For purposes of simplification in the drawings, the individual contact terminals have not been illustrated in the insulator modules 20 shown in F GS. 2 through 13.

FIGS. 3 through 9 illustrate the details of construction of the presently preferred insulator modules 20. Each of the modules 20 comprises a unitary block of insulation material which is preferably but not necessarily rigid. Although the present invention is, of course, not in any way limited to the use of a particular material for the insulator modules, one material which has been found suitable from the standpoint of being inexpensive, light in weight, strong in impact and tensible strength, resistant to deformation under load and of superior flame resistance, is cellulose acetate.

Each insulator module 20 has a rear 42 and a front 44, and is of generally rectangular cross-section. The module 20 may be generally considered as comprising a rearward body portion 46 within which the contact terminals are supported, and a forward engaging portion 48 within which the contacts are shielded and which is adapted for interengagement with an opposed, axially aligned module which has been turned about the axis of alignment, as best illustrated in FIG. 3 of the drawings, each block 29 includes opposite parallel sides 50 and 52, and opposite parallel ends 54 and 56, with the corners where the respective sides and ends meet preferably being rounded as shown in the drawings. The presently preferred modules 24) have sides 50 and 52 which are twice the width of the ends 54 and 56. This makes it possible to stack the modules not only side-by-side and end-to-end, but also to stack the side of one module against the ends of a pair of modules which are in side-by-side relationship, while still maintaining a desired rectangular shape of the stack. It will thus be apparent that the rectangular cross-sectional shape of the modules, with sides 50 and 52 which are twice the length of the ends 54 and 56, permits an almost endless variety of stacked combinations where a plurality of the modules are employed.

The rearward body portion 46 of the module 20 within which the contact terminals are supported comprises a generally solid body of the insulating material with axial passages therethrough for receiving the terminals, while the forward engaging portion 48 of the module generally comprises a series of interrelated external and internal wall members for housing the interengaging portions of the contact terminals and for separating the contact terminals from each other, and also for providing a secure, polarized physical connection between opposed pairs of the modules which are interengaged. Accordingly, the front of the rearward body portion of the module is generally defined by a forwardly facing surface 58. This forwardly facing surface 58 is generally disposed in a transverse plane, but if desired, the peripheral regions thereof may be slightly higher or forwardly disposed relative to the internal portions thereof so as to insure a complete peripheral closure when the modules are interengaged, and if desired, to permit slightly raised identifying numbering or lettering at the front edges of the walls forming the forward engaging portion 48.

Referring now to the forward engaging portion 48 of module 20, the various external and internal walls comprising the forward engaging portion 48 are all integrally molded with the rearward body portion 46 so as to extend axially forwardly from the rearward body portion 46. The particular combination of walls forming the forward engaging portion 48 illustrated in the drawings is adapted to accommodate six pairs of contact terminals, or a total of twelve terminals. It is to be understood, however, that other wall configurations will be employed where the module is adapted to support a different number of contact terminals. For example, where five pairs of contact terminals, or ten individual contact terminals, are to be supported in the module, the wall configuration will be varied so as to accommodate the five pairs, while at the same time completely enclosing the contacts in the external walls, and completely separating the contacts from each other by means of the internal walls. The external walls for five pairs of contact terminals will normally be substantially the same as the external walls for six pairs, but the number of internal walls required for five pairs is only three as compared with four for six pairs of contact terminals. It will be appreciated that any number of contact terminals may thus be accommodated, by varying the number of internal walls provided in the forward engaging portion 48 of each individual module 20.

Referring at first to the external walls, at the side 50 of the module is a side wall which extends from the end 54 of the module along one-half of the width of side 50. The forwardly facing surface 58 defining the front of the rearward body portion 46 is exposed along the remainder of side 50. Thus, when two opposed modules are interengaged, as oriented in FIG. 3, with the side walls 56 of both modules at the same side of the combination, the two side wall portions 66 of the modules will move to overlapping positions so that the center edge 61 of one wall 60 will be immediately adjacent to the center edge 61 of the other wall 60, thereby providing complete enclosure of the side 5!).

Along the other side 52 of the module, a similar side wall 62 extends from the other end 56 halfway along the side 52 so as to terminate at center edge 63. Thus, when a pair of the modules are interengaged from the aligned positions of FIG. 3, the respective side wall portions 62 will move to overlapping positions with their center edges 63 immediately adjacent to each other, so as to completely enclose the side 52 of the combination.

The end enclosure is accomplished by providing a single end wall 64 along the end 56 of the module, extending from the side wall 62 and terminating at an edge 65 which is spaced from the side 56 approximately the thickness of the side wall 6t) to accommodate the side wall 60 of an opposing module. Space is provided proximate the other end 54 so that when the module is engaged with an op posing module in the manner suggested in FIG. 3, the end wall 64 of each of the modules will move forwardly to the forwardly facing surface 58 of the rearward body portion 46 in alignment with the end 54 of the opposing module, thus completely enclosing the ends 54 and 56 of the combination. In this manner, the side walls 61) and 62 and the end wall 64 combine with the respective side walls 60 and 62 and end wall 64 of an opposing module a so as to provide complete external enclosure of the contacts when the modules are operatively interengaged.

It is to be noted that by providing one of the side walls 60 in the half of the module adjacent to end 54, and the other side wall 62 in the other half of the module adjacent to end 56, the external walls of a pair of engaged modules function as alternating tongues and grooves all of the way around the peripheries of the modules so as to obtain an excellent tongue-and-groove type of physical interlocking between the modules.

Referring now to the inner walls of the forward engaging portion 43 of the module, these inner walls comprise transverse separator wall members which extend transversely from the respective side walls 60 and 62, parallel to the ends 54 and 56, and terminate at their free edges short of the respective opposite side walls 52 and 50 a distance corresponding approximately to the thickness of the respective outer side walls 62 and 61 so as to provide room for the respective side walls 62 and 60 of an opposed insulator module.

In the embodiment of the module shown in the drawings wherein six pairs of contact terminals are supported in the module, four of the transverse separator walls are provided, two in each half of the module. Thus, extending transversely from the side wall 69 are a pair of tranverse separator walls 66 and 68, and extending transversely from the side wall 62 are a pair of transverse separator walls 7t? and 72.

As best illustrated in FIG. 4, these transverse separator walls are so arranged and spaced that they will intermesh upon engagement of a pair of the modules along the axial line suggested in FIG. 3. Thus, as best shown in FIG. 4, the transverse separator wall 66 is spaced downwardly from the end 54 so as to provide a recess 74 to receive the end wall 64 of a complementary module. The transverse separator wall 68 is spaced downwardly from separator wall 66 so as to provide a recess 76 within which the transverse separator wall 72 of a complementary module will be received. The transverse separator wall 70 is likewise spaced downwardly from the separator wall 68 so as to provide a recess 78 within which the separator wall 76 of a complementary module will be received. Similarly, the transverse separator wall 72 is: spaced downwardly from the separator wall 74) to provide space within which the separator wall 68 of an opposed module will fit. Finally, there is a recess 82 between the transverse separator wall 72 and the end wall 64 for receiving the separator wall 66 of an opposing module.

Six pairs of axial contact terminal-receiving passages or holes 84- extend through the rearward body portion 66 of the module, and each pair of the passages 84 has its axis generally aligned with a surface of one of the transverse separator walls 66, 63, 76' or 72;, each pair of the passages 84 continuing as grooves 36 in a surface of one of the transverse separator walls. When a pair of complementary modules are engaged in accordance with the alignment of FIG. 3, respective pairs of the grooves 86 in one module will register with respective pairs of the grooves 86 of the other module, so as to provide substantially completely enclosed passages between adjacent pairs of the separator walls of the respective modules within which the forward engaging portions of the contact terminals are disposed, whereby to substantially completely encase each of the mating pairs of contact terminals in the insulation material of the engaged modules.

in the preferred embodiment of the invention, the passages 84 and grooves 86 have axially arranged guide slots 88 in the sides thereof for guiding and supporting the edges of the prefered contact terminals employed with the invention, which comprise generally fiat, elongated metallic strips. Within the rearward body portion 46, the passages 84 are provided with respective rearwardly facing shoulders 96 to provide stop means limiting the forward extent of travel of the contact terminals when the contact terminals are inserted into the passages through the rear 42 of the module. Further, the passages 84 within the rearward body portion 46 are provided with respective forwardly facing shoulders 92 against which spring locking fingers on the respective contact terminals latch so as to hold the contact terminals in their operative positions in the module when they are inserted into the passages from the rear 42 of the module.

The modules are provided at their sides 50 and 52 and ends 54 and 56 with a series of alternately spaced projections 94 and recesses 96. When a pair of the modules are brought together side-by-side, end-to-end, or end-to-side,

the projections 94 and recesses 96 on the fiat contacting surfaces of the modules will be enterengaged so as to lock the modules in proper stacked position. These interengaging projections 94 and recesses 96 serve the dual function of greatly facilitating proper orientation of the modules as they are being stacked together, and of looking and holding the modules in their proper stacked positions when the modules are operatively positioned within the receptacle and plug connector members They also cooperate with strap means hereinafter described for snapping one or more modules into the receptacle and plug shells and retaining them in operative position in the shells.

The projections 94 and recesses 96- alternate around the entire periphery of the rearward body portion 46 of the module, with one projection 94 and one recess 96 being disposed on each of the ends 54 and 56 of the module, and with two projections 94 and two recesses 96 being disposed on each side 59 and 52. The arrangement is such that a projection-recess pair is provided on each module end 54 and 56, and two projection-recess pairs are provided on each side 50' and 52 of the module, so that a total of six projection-recess pairs are provided. All six projection-recess pairs have the same spacing between the projection and the recess.

Thus, regardless of whether the modules are stacked together sideoy-side, end-to-end, or end-to-side, at least one pair of the projections 94 and recesses 96 will be interengaged, thereby fixing the modules against both transverse shifting and angular misalignment.

Refering now to FIGS. and 11, three of the modules are illustrated in side-by-side stacked relationship, with a pair of mounting straps 98 shown spaced from the stack of modules but in position to be moved toward the stack and snapped over the modules so as to hold the modules together in this stacked relationship and so as to provide means for snapping the stack of modules into either the receptacle shell or the plug shell. The two straps 98 are preferably composed of a resilient material, such as spring metal, and are of identical construction. The size of the straps 98 will depend on the number of modules in the stack, and the arrangement of the modules therein. However, the preferred straps 98 for a side-by-side stack of three modules as illustrated comprises an elongated base portion 100 adapted to span across the three ends of the modules, a relatively long leg portion 102 extending at right angles from one end of the base portion 1G0, and a relatively short leg portion 104 extending at right angles from the other end of the base portion 160.

Three openings 1% are provided through the base portion 100 of each strap 98 so as to receive the respective three projections 94 on the ends of the modules against which the base portion 100 lies in operative position. The relatively long leg portion is provided with two openings 1% to receive the two projections 94 on the side of the module against which it lies in the operative position. The relatively short leg portion 104 is provided with an inwardly projecting bead 108 formed by denting the strap from the outside, this bead 108 being engageable in the complementary recess 96 in the side of the module engaged by the relatively short leg portion 104.

Thus, the mounting straps 98 may be generally described as being U-shaped, with a base and a relatively long leg portion and a relatively short leg portion. These mounting straps easily snap over the stacl; of modules, and securely hold the stack together, the interengaging projections 94 and recesses 96 at the interfaces between adjacent modules holding the modules secure relative to each other.

Each of the mounting straps 98 is provided with a spring finger 110 which inclines forwardly and outwardly, these spring fingers 110 snapping behind corresponding shoulders in the receptacle and plug shell members so as to permit the entire combination to be snapped into operative positions in the receptacle and plug shells.

FIGS. 12 and 13 illustrate similar U-shaped mounting straps 98a adapted to be snapped over the rearward body portion 46 of a single insulator module 20, the straps 98a having short base portions ltlda, relatively long leg portions 1122a and relatively short leg portions 104a, and each having openings lltitia and a projecting bead 108a for securing the straps about the module when they are snapped into place. The straps 98a also include respective spring fingers 11a for engagement with respective shoulders in receptacle and plug shells designed for a single insulator module.

The presently preferred receptacle shell construction is illustrated in detail in FIGS. 14-17, inclusive, the receptacle shell 16 including a tubular rear portion 112 of rectangular cross-section and a similar tubular forward portion 114 of rectangular cross-section, the forward portion 114 being somewhat larger than the rear portion 112 so as to accommodate the plug shell therein. The insulator modules with the straps 98 thereon are adapted to be received within the rear shell portion 112, being moved into position through the open front of shell 16, and an inwardly directed flange 116 is provided at the rear of shell 16 as a seat against which the mounting straps 98 and modules 20 rest. A pair of rectangular apertures 118 are provided through the wall of receptacle shell 16 in the rear portion 112 thereof so that when the stacked modules with the mounting straps $8 thereon are shoved into the receptacle shell the spring fingers of mounting straps 98 will register with apertures 118, the fingers 116/ snapping outwardly so as to be engageable against the rearwardly facing shoulders 12b in the apertures 118, thus securely locking the modules and mounting straps in position. By providing apertures 118 which extend through the wall of the receptacle shell, a suitable tool may be inserted through the apertures 118 so as to flatten the spring fingers 11d and permit withdrawal of the modules and mounting straps.

FIGS. 18, 19 and 19a illustrate details of construction of a presently preferred plug shell 28. Shell 23 includes .a tubular forward portion 122 which is axially slidably engageable within the enlarged portion 114 of the re ceptacle shell 16. A forwardly facing shoulder 124 is provided at the rear of the forward portion 122 of the plug shell as a seat for the insulator modules and attached mounting straps 98. Apertures 126 having rearwardly facing shoulders 123 are provided through the wall of the tubular forward portion 122, and serve the same purpose as the corresponding apertures 118 and shoulders 12% in thereceptacle shell.

The plug shell 28 includes a rear housing portion 130 which serves as a shield to cover the rear of the modules and the contact terminals, the plug shell including a downwardly projecting housing portion 132 having an opening 134 therethrough for receiving the conductor cable 38. The downwardly projecting portion 132 of the housing includes a passage 136 which is generally axially arranged relative to the plug receptacle shell 28 and which communicates with the opening 134 through which the cable extends. A clamp member 133 is slidable in passage 13s and is adapted to be moved into clamping engagement with the cable by actuation of a screw member 146 threadedly engaged in passage 136.

This secure clamping of the cable in the plug shell, and also the enclosure of the rear portions of the modules, the contact terminals and the exposed cable conductors, are desirable in the case of the plug connector member which is normally contemplated to be a movable, exposed member. However, in the case of the receptacle member shown and heretofore described, it is contemplated that it will be mounted on a panel or wall, with the flange portion 22 and the forward opening thereof exposed, but with the rear portion of the receptacle shell disposed behind the panel or wall. Accordingly, the cable conductors in the case of the receptacle connector member merely enter the connector member through the open rear end thereof as defined within flange 116, and no housing or clamping means is provided.

It is to be understood that the particular receptacle and plug shell constructions herein described and shown in the accompanying drawings are merely preferred embodiments for a panel or wall installation, and that various receptacle and plug shell constructions may be employed in connection with the insulator modules, mounting straps and contact terminals as defined herein without departing from the present invention.

The presently preferred contact terminals employed in connection with the insulator modules hereinabove described are illustrated in FIGS. 20-24, inclusive, of the drawings, these contact terminals of similar character to the contact terminals described and claimed in my said copending application Serial No. 792,287 for Electrical Connector as above stated.

The preferred contact terminals 142 have several important characteristics which permit a new and unusual cooperation between the contact terminals and the insulator modules of the present invention. For one thing, these contact terminals are of the snap-in type wherein the conductor is crimped or soldered to the contact terminal before the contact terminal is placed in the insulator, and then the contact terminal is merely pushed amasso into a contact terminal-receiving passage in the insulator. This is important in the present invention wherein the insulator modules 29 are each molded as an integral body of insulation material, with the contact terminal-receiving passages formed therein. Another advantage of the contact terminals 142 which is of particular importance is that these contact terminals, like the insulator modules 20, are of hermaphrodite construction. Thus, not only are all of the modules of identical construction, whether they are in the receptacle or in the plug, but also all of the contact terminals may be of identical construction, each contact terminal performing the function of both pin and socket. This facilitates the assembly of the connectors and greatly increases the flexibility of the connectors for various uses. The particular contract terminals 142, like the modules, are adapted to engage each other when they are positioned in opposed relationship, and turned 180 relative to each other about their longitudinal axes. Thus, when the contact terminals are installed in exactly the same manner in a pair of the modules, and the modules are positioned as in FIG. 3 of the drawings, not only will the modules mate, but also the individual pairs of opposed contact terminals will mate.

A further advantage of the particular contact terminals 142 is that the contacting surfaces thereof comprise inclined spring fingers which, when engaged, tend to draw the engaged pair of contact terminals together. This provides an excellent latching action between opposed, mating pairs of contact terminals, so as to hold the insulator modules and the receptacle and plug shells together under normal, vibratory conditions, thus in most instances eliminating the necessity for any separate mechanical latching device between the receptacle and the plug. However, it is to be understood that such a separate accessory latching device may be provided between the receptacle and the plug where excessive cable stresses might tend to disengage the plug from the receptacle.

Other advantages of these contact terminals 142 are that they have an unusually large contact engaging surface area and a built-in wiping action, thus providing excellent electrical characteristics. Also, these contact terminals, like the modules, are produceable in a single operation, as by stamping.

Referring to the details of construction of one of the contact terminals 142, the contact terminal comprises a unitary strip of conducting material, normally metal, having a generally fiat body portion 144, with the contacting portions comprising three spring fingers extending forwardly from the body portion 144 in side-by-side relationship, there being a middle spring finger 146 and a pair of side spring fingers 148 disposed on opposite sides of the middle finger 14-6. Each of the spring contacting fingers is provided with a generally forwardly facing, inclined entrance ramp 150 at its free end, the entrance ramp 150 of the side fingers 148 facing toward one side of the contact terminal, and the entrance ramp 150 of the middle spring finger 146 facing toward the opposite side of the contact terminal. Extending rearwardly from the entrance ramps are inclined back ramps 152 which provide the actual contacting surfaces when the contact terminals are interengaged. The back ramp 152 of the side spring fingers 148 will engage respective back ramps 152 of the side fingers 143 of a complementary contact terminal, while the back ramp 152 of the middle finger 146 will engage the corresponding back ramp 152 of the middle spring finger 146 of the complementary contact terminal, the spring fingers being flexed when engaged so as to tend to draw the opposed contact terminals together.

Each contact terminal 142 is further provided with a spring locking finger 154 which inclines rearwardly and outwardly from the fiat body portion 144, being conveniently cut out from the center of body 144. This spring locking finger 154 is adapted to snap outwardly in front of the forwardly facing shoulder 92 and the re- 10 spective contact-receiving passage 84 of the module when the contact terminal is pushed forwardly into the passage 54 with the side edges of the body 144 of the contact terminal slidably engaged in the guide slots 88 in the sides of the respective passage 84.

Also formed outwardly from the body 144 of contact terminal 142 is a tab 156 which engages against the rearwardly facing shoulder of the respective contact terminal-receiving passage 84 so as to limit the forward positioning of the contact terminal in the passage.

To the rear of body portion 144 of contact terminal 142 is a crimping portion 158 adapted to be crimped about the end of a respective conductor. Lances 160 in the crimping portion 158 are adapted to pierce through the insulation of the conductor and make physical and electrical contact with the conductor wire.

As shown in FIG. 23, even when the modules are separated, the forward engaging portions of the contact terminals 1 .2 are shielded and prevented from being damaged by the outer side walls 60 and 62 and the end wall 64, and by the transverse separator walls 66, 68, 70 and 72, comprising the forward engaging portion 48 of the module, the forward engaging portions of the contact terminals 42 being partially recessed in respective grooves 86 of the transverse separator walls. When a pair of the modules are operatively engaged as shown in FIG. 24, the forward engaging portions of the contact terminals 142 are completely enclosed, not only within the side walls 60 and 62. and end wall 64 of the modules, but also they are individually enclosed within the grooves 86 of adjacent transverse separator walls, thus not only shielding the contact terminals from external conditions, but also providing an excellent guard against flashover either between adjacent contact terminal pairs or between the contact terminals of one module pair and those of another module pair.

FEG. 25 of the drawings illustrates various arrangements of one, two, three or four of the modules as they may be embodied in a receptacle or plug connector member. FiG. 25 is diagrammatic in character, the modules being viewed from the front, with one-half of each module being shOWn in blank and with the other half characterized by an X. It will be seen from FIG. 25a that a single module may assume two positions. HG. 25b illustrates that a pair of modules may be disposed in any one of eight different positions. In FIG. 25c three insulator modules are shown in 24 different positions. In PiG. 25d four of the modules are shown in 80 different positions. If a larger number of modules are combined, the resulting number of possible combinations will be extremely large in number. It is to be noted that in FIGS. 25a, b, c, and d, a rectangular or square configuration has been retained in each example. Even further combinations could be provided by orienting the modules so as to produce other external shapes.

While the instant invention has been shown and described herein, in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is therefore not to be limited to the details disclosed herein, but is to be accorded the full scope of the claims.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An insulator for an electrical connector which is mateable with another insulator of like construction, comprising: a rear body portion having a plurality of terminal-receiving passages therethrough, and a forward engaging portion integral with and extending forwardly from said body portion, said engaging portion including wall means for shielding forward contacting portions of terminals adapted to be mounted in said passages of said body portion; said insulator comprising two halves on opposite sides of a plane extending axially through said body and engaging portions, the two halves of said body portion being generally bilaterally symmetrical on opposite sides of said plane, and the two halves of said en gaging portion being generally bilaterally complementary on opposite sides of said plane; said wall means including a first wall member in one of said halves of said engaging portion disposed in offset relationship to a first one of said passages in the same half of said body portion and having a groove therein which is in general alignment with said first passage; and a second wall member in the other half of said engaging portion disposed in offset relationship to a second of said passages which is arranged in bilateral symmetry to said first passage, said second wall member having a groove therein which is in general alignment with said second passage; each half of said engaging portion being mateable with the other half of said engaging portion of an insulator of like construction so that said first and second passages of one of the engaged pair of insulators will be aligned respectively with said second and first passages of the other insulator, with said first and second wall members of one insulator being adjacent respectively to said second and first wall members of the other insulator, said grooves in adjacent wall members facing each other whereby adjacent pairs of said grooves form continuations of the respective passages for enclosing forward contacting portions of terminals adapted to be mounted in the passages.

2. An electrical connector member which comprises: a shell having a rear end and an open front end, and having a tubular insulator-receiving portion of rectangular cross-section between said ends; rearwardly facing shoulder means in said tubular portion of the shell; an insulator block having a front and a rear and having a terminal-receiving passage extending axially therethrough from the rear to the front, said insulator block having a rectangular cross-section slightly smaller than that of the inside of said tubular portion of the shell; and a pair of like U-shaped strap members of spring material, each strap member conforming in shape to slightly less than half of the periphery of the insulator block, said strap members being resiliently engageable about opposite half portions of the periphery of the block; interengageable projections and recesses on the block and the strap members for locking said strap members in their engaged positions about the block; and a spring finger extending forwardly and outwardly from one of said strap members, said spring finger being engageable with said shoulder means to latch the insulator block in position in the shell when the block with the attached straps are inserted into the shell through its front end.

3. An electrical connector according to claim 2 wherein said insulator block comprises a plurality of stacked modular insulator members, each insulator member comprising a body of insulating material having a front and rear and having a terminal-receiving passage extending axially therethrough from the rear to the front, said body being of rectangular cross-section with the peripheral surfaces thereof comprising parallel side surfaces and parallel end surfaces, and a plurality of spaced aligning projections and recesses alternately arranged in the same axial position around the periphery of said body, said projections and recesses of each insulator module being engageable with complementary projections and recesses of an adjacent module in the stack so as to hold the adjacent modules in alignment; each of said strap members having a plurality of holes therein within which respective said insulator module projections fit for looking the strap members in place about said block.

4. An insulator for an electrical connector which is mateable with another insulator of like construction, comprising a rear body portion having a plurality of terminalreceiving passages therethrough, and a forward engaging portion integral with and extending forwardly from said body portion, said engaging portion including wall means for shielding forward contacting portions of terminals adapted to be mounted in said passages of said body portion, said insulator comprising two halves on opposite sides of a plane extending axially through said body and engaging portions, the two halves of said body portion and said passages therein being generally bilaterally symmetrical on opposite sides of said plane, and the two halves of said engaging portion being generally bilaterally complementary on opposite sides of said plane, each half of said engaging portion being mateable with the other half of said engaging portion of an insulator of like construction so that said wall means of the mated pair of insulators forms a substantially complete enclosure for the forward contacting portions of terminals adapted to be mounted in said passages, said wall means including a pair of bilaterally complementary "wall members in the respective halves of said engaging portion of the insulator, said wall members extending forwardly in offset relationship to a respective bilaterally symmetrical pair of said passages in the respective halves of the body portion, said Wall members having respective bilaterally complementary grooves therein which communicate with the respective said passages, whereby when two of said insulators are mated the Wall member in each half of one insulator will be disposed adjacent to the wall member in the other half of the other insulator member, withthe opposed grooves in each adjacent pair of walls forming substantially enclosed continuations of the respective said passages for housing forward contacting portions of terminals adapted to be mounted in the passages.

5. An insulator for an electrical connector which is mateable with another insulator of like construction, comprising a rear body portion of rectangular cross-section having a plurality of terminal-receiving passages therethrough, the peripheral surfaces of the body portion comprising parallel side surfaces and parallel end surfaces, the sides being twice as wide as the ends, a forward engaging portion integral with and extending forwardly from said body portion, said engaging portion including wall means for shielding forward contacting portions of terminals adapted to be mounted in said passages of'said body portion, said insulator comprising two halves on opposite sides of a plane extending axially through said body and engaging portions parallel to said end surfaces so as to bisect said side surfaces, the two halves of said body portion being generally bilaterally symmetrical on opposite sides of said plane, and the two halves of said engaging portion being generally bilaterally complementary on opposite sides of said plane, each half of said engaging portion being mateable with the other half of said engaging portion of an insulator of like construction so that said wall means of the mated pair of insulators forms a substantially complete enclosure for the forward contacting portions of terminals adapted to be mounted in said passages, and a plurality of spaced aligning projections and recesses alternately arranged in the same axial position around the periphery of said body portion of the insulator, the projections and recesses being arranged in projection-recess pairs each having the same spacing between the projection and recess, with one projectionrecess pair on each end and two projection-recess pairs on each side, the pair on one end being complementary to the pair on the other end, and the pairs on one side being complementary to those on the other, whereby a plurality of said insulators may be stacked side-by-side, end-to-end and end-to-side with complementary projection-recess pairs of adjacent insulators mating so as to hold the insulators in alignment.

6. An insulator for an electrical connector which is mateable with another insulator of like construction, comprising a rear body portion of rectangular cross-section having a plurality of terminal-receiving passages therethrough, the peripheral surfaces of the body portion comprising parallel side surfaces and parallel end surfaces, the sides being twice as wide as the ends, and a forward engaging portion integral with and extending forwardly from said body portion, said engaging portion including wall means for shielding forward contacting portions of terminals adapted to be mounted in said passages of said body portion, said insulator comprising two halves on opposite sides of a plane extending axially through said body and engaging portions parallel to said end surfaces so as to bisect said side surfaces, the two halves of said body portion being generally bilaterally symmetrical on opposite sides of said plane, and the two halves of said engaging portion being generally bilaterally complementary on opposite sides of said plane, each half of said engaging portion being mateable with the other half of said engaging portion of an insulator of like construction so that said Wall means of the mated pair of insulators forms a substantially complete enclosure for the forward contacting portions of terminals adapted to be mounted in said passages, said wall means including a peripherally arranged portion with a part thereof aligned with each of said side surfaces and a part thereof aligned with at least one of said end surfaces, so that the peripherally ar ranged Wall portions of a mated pair of the insulators substantially completely circumscribe said forward engaging portions of the pair of insulators, and said wall means further including a pair of bilaterally complementary internal Wall members in the respective halves of said engaging portion of the insulator, said wall members extending forwardly parallel to said end surfaces and in slightly olfset relationship to a respective bilaterally symmetrical pair of said passages in the respective halves of the body portion, said internal Wall members having rc-- spective bilaterally complementary grooves therein which communicate with the respective passages, whereby when two of said insulators are mated the said internal wall member in each half of one insulator will be disposed adjacent to the wall member in the other half of the insulator member, with the opposed grooves in each adjacent pair of walls forming substantially enclosed continuations of the respective said passages for individually housing forward contacting portions of terminals adapted to be mounted in the passages.

7. An insulator for an electrical connector as defined in claim 6 wherein a pair of said internal Wall members are provided in one half of said engaging portion of the insulator, said grooves being in the sides of said pair of walls which face each other, the said internal wall member in the other half of said engaging portion of the insulator having one of said grooves on each side thereof and being bilaterally complementary to said pair of internal Walls, so that when two of said insulators are mated the said pair of internal walls in one half of each insulator member will be disposed adjacent to and on opposite sides of said internal -:wall in the other half of each insulator member.

References Cited in the file of this patent UNITED STATES PATENTS 526,078 Henck Sept. 18, 1894 1,747,896 Gates Feb. 18, 1930 1,869,566 Krahl Aug. 2, 1932 2,221,710 Johnson Nov. 12, 1940 2,397,102 Graham Mar. 26, 1946 2,469,397 Mezek May 10, 1949 2,497,523 Warkentin Feb. 14, 1950 2,838,739 Winkler June 10, 1958 2,888,660 Fox May 26, 1959 FOREIGN PATENTS 586,049 France Sept. 18, 1924 791,913 Great Britain Mar. 12, 1958 

2. AN ELECTRICAL CONNECTOR MEMBER WHICH COMPRISES: A SHELL HAVING A REAR END AND AN OPEN FRONT END, AND HAVING A TUBULAR INSULATOR-RECEIVING PORTION OF RECTANGULAR CROSS-SECTION BETWEEN SAID ENDS; REARWARDLY FACING SHOULDER MEANS IN SAID TUBULAR PORTION OF THE SHELL; AN INSULATOR BLOCK HAVING A FRONT AND A REAR AND HAVING A TERMINAL-RECEIVING PASSAGE EXTENDING AXIALLY THERETHROUGH FROM THE REAR TO THE FRONT, SAID INSULATOR BLOCK HAVING A RECTANGULAR CROSS-SECTION SLIGHTLY SMALLER THAN THAT OF THE INSIDE OF SAID TUBULAR PORTION OF THE SHELL; AND A PAIR OF LIKE U-SHAPED STRAP MEMBERS OF SPRING MATERIAL, EACH STRAP MEMBER CONFORMING IN SHAPE TO SLIGHTLY LESS THAN HALF OF THE PERIPHERY OF THE INSULATOR BLOCK, SAID STRAP MEMBERS BEING RESILIENTLY ENGAGEABLE ABOUT OPPOSITE HALF PORTIONS OF THE PERIPHERY OF THE BLOCK; INTERENGAGEABLE PROJECTIONS AND RECESSES ON THE BLOCK AND THE STRAP MEMBERS FOR LOCKING SAID STRAP MEMBERS IN THEIR ENGAGED POSITIONS ABOUT THE BLOCK; AND A SPRING FINGER EXTENDING FORWARDLY AND OUTWARDLY FROM ONE OF SAID STRAP MEMBERS, SAID SPRING FINGER BEING ENGAGEABLE WITH SAID SHOULDER MEANS TO LATCH THE INSULATOR BLOCK IN POSITION IN THE SHELL WHEN THE BLOCK WITH THE ATTACHED STRAPS ARE INSERTED INTO THE SHELL THROUGH ITS FRONT END. 